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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 420 |
| 8 | 3360 |
| 9 | 30240 |
| 10 | 403200 |
| 11 | 4019400 |
| 12 | 80166240 |
| 13 | 965284320 |
| 14 | 12173441280 |
| 15 | 162850287600 |
| 16 | 2428557331200 |
| 17 | 32123543612160 |
| 18 | 534678700308480 |
| 19 | 8126981741380320 |
| 20 | 128338880777251200 |
| 21 | 2080312367956502400 |
| 22 | 36351373041072122880 |
| 23 | 606331931399062693440 |
[0,0,0,0,0,0,420,3360,30240,403200,4019400, 80166240,965284320,12173441280,162850287600, 2428557331200,32123543612160,534678700308480, 8126981741380320,128338880777251200, 2080312367956502400,36351373041072122880, 606331931399062693440] |